Pertinent existing art relating to pulverizer throat designs are Schwartz, U.S. Pat. No. 2,275,595; Bailey et al, U.S. Pat. No. 2,378,681; Ebersole, U.S. Pat. No. 2,473,514; and Bice, U.S. Pat. No. 2,545,254, all of which are assigned to the Babcock & Wilcox Company, assignee of the present invention. Schwartz, '595, discloses curved annular passages forming a throat discharging scavenging air in the direction of the grinding elements. Bailey et al, '681, discloses a design for constant air velocity through the throat. Ebersole, '514, discloses an adjustable throat, and Bice, '254, discloses an eccentric throat design for air distribution. The prior art is indicative of a need to solve the problems associated with the pulverization and transport of solid materials at minimum capital, maintenance and operating costs involving air pressure losses, excessive dribble of solid material downward through the throat and erosion of surfaces in contact with the transport of solid material.